Once returned back to her home, Helen regains control. Despite Anne’s warnings that she’s just testing them, and the family’s assertions that they wouldn’t indulge in her little games, they start to baby her again, and Anne watches as a lot of her work is slowly being destroyed. Helen throws a pitcher of water at Anne, and Anne is fed up. She grabs Helen, dragging her to the water pump to force her to refill the pitcher. The Captain rises to stop her, but James, his stepson, finally stands up to his father, and explains to the family that they need to trust her and let her do her work.
In the yard, Anne has the water pump running, and angrily spells out ‘water’ into Helen’s palm. As if someone turned on a switch inside of her, Helen understands. She has the breakthrough that Anne had been searching for. She flies about, touching things, begging to know their names. Anne obliges, in tears, and calls out for the family to come see. As they come into the scene, she rushes up to them, demanding what words are associated with them, and learns ‘mother’ and ‘father’. Then she rushes back to Anne, wanting to know her title. Anne shows her ‘teacher.’ Helen, in a seemingly understanding gesture, retrieves the keys from her mothers side and gives them to Anne. The play ends with Anne writing down in her journal “I love Helen…forever and ever.”